Work holding devices for use in machine tool operations are part of an old and highly developed art and it is known to generally provide for such chucking devices which are self-centering to position the work piece relative to the axis of rotation of the machine tool and chucking device and also for indexing devices which can be used in connection with multiple jawed chucking devices to facilitate multiple axis machining. Devices of this general type are not always suitable for the high speeds of modem machine tools to provide the desired reliability. It is also known in the prior art to use draw bars and draw tubes to effect actuation of chuck jaws and accessory devices but all of such prior art is not been developed for high speed multiple axis auto indexing of machine tools as is required for today's complex machine tool center operations.